In commercial bakeries, baking mixes such as cake batters, pastries, desserts, frostings, decorating materials and other materials are used in high volume production of light breads and desserts. In such high volume production, baking materials usually are loaded into a large mixing bowl and mixed utilizing commercial mixing machines. The mix is then dispensed from the bowl, for example, into cake tins or onto cakes or pastries.
Most basic ways to dispense mix from a mixing bowl into a cake tin include tipping the bowl and pouring the bowl contents into the tin and dipping a measuring cup into the bowl to fill the cup with mix which can then be poured from the cup into the tin. Since large commercial mixing bowls may be greater than two feet in diameter at the top and may weigh over three hundred pounds when full of mix, pouring the mix from the bowl is not practical. Further, in high volume commercial applications, manually dispensing mix from the bowl utilizing a ladle or a cup requires too much time and is inefficient.
In high volume commercial applications, hoppers sometimes are utilized to facilitate more quickly dispensing mix. With a hopper structure, a mixing bowl full of mix is lifted to the top of the hopper and the mix is poured from the bowl into the hopper. The mix then is dispensed from the hopper at an outlet located at a lower section of the hopper. Specifically, gravity forces acting on the mix cause the mix to flow out of the hopper outlet when the outlet is open.
Although hoppers improve productivity in a high volume applications as compared to manually dispensing the mix, there are a number of disadvantages associated with utilizing a hopper. For example, mixing bowls generally are heavy, and when loaded with mix, may weigh more than three hundred pounds. Lifting a bowl full of mix to the top of the hopper, which may be four to six feet above the ground, requires considerable effort and is dangerous. In addition, once no more of a particular mix in the hopper is required, the mix remaining in the hopper must be removed and the hopper must be cleaned and prepared for a different type of mix. Cleaning a large hopper, including its dispensing mechanism, can be time consuming. Gravity feed of mix through the hopper outlet also is a constraint on the speed of operations since the gravity forces acting on the mix generally cannot be increased to increase the rate of mix flow.
Dispensing pumps for dispensing mix directly from a mixing bowl also are known. A typical dispensing pump includes a piston and cylinder assembly and a discharge tube. In operation, an inlet of the pump is placed in the mixing bowl. Pressure forces created by the piston draw mix from the bowl, through the pump inlet, and into the discharge tube. Once the discharge tube is full of mix, and as more mix is drawn into the discharge tube from the bowl, mix is forced through the tube outlet.
The above described pump eliminates having to lift a heavy bowl above a hopper and cleaning of the hopper. With such a pump, however, when changing mix, the discharge tube must be cleaned. Such tubing can be rather lengthy and difficult to clean. In addition, since the discharge tube must first be filled with mix in order to force mix through the tube outlet, the discharge tube is filled with mix at the time no more mix is required to be dispensed. The mix in the discharge tube typically is discarded as part of the cleaning process. Since the discharge tube is lengthy, a substantial amount of mix is wasted. Further, the piston of such a pump usually operates at a high pressure to create the air forces necessary to compress the mix and reduce air entrainment. Operating a piston at such high pressures can be dangerous and workers must take extra safety precautions to avoid injury when working with such a device.
A commercially successful dispensing device is described in U.S. Pat. No. 4,170,253. Our father, Donald A. McArthur, is the inventor of the device described and claimed therein. U.S. Pat. No. 4,170,253 is hereby incorporated by reference herein. With our father's invention, an outlet is formed at a bottom portion of a mixing bowl and the dispensing device is mounted below the mixing bowl and attached to the bowl outlet. A dispensing tube receives mix from the bowl by gravity-assisted feed. A piston moves mix through the dispensing tube to the tube outlet. Relatively short lengths of dispensing tubing are utilized by the device
Our father's invention has proven extremely useful. One great advantage is that no high pressure piston is required to draw mix into the tube. Therefore, the device is relatively safe to use as compared to other pumps. As with the gravity feed in hopper constructions, however, the gravity-assisted feed of mix from the bowl to the dispensing tube limits the flexibility and operation speed of the device. For example, flexibility is limited since a mixing bowl cannot be placed below the dispenser. In addition, particularly when working with a thick mix, such mix will not flow through the bowl outlet into the dispensing tube merely by gravity-forces and any other forces created by operation of the piston. The mix has to be forced, manually, through the bowl opening and into the tube. Once the tube is filled with mix, i.e., primed, then operations can be initiated. Such manual priming is time consuming.
Accordingly, it is desirable and advantageous to provide a dispensing assembly for high volume applications which utilizes controllable forces, other than or in addition to gravity forces, in connection with dispensing mix from a bowl. It is also desirable and advantageous to provide an assembly which is self-priming even when utilizing thick mix, flexible so as to enable placement of the mixing bowl above or below the dispensing device, and safe to utilize.
An object of the present invention is to provide a dispensing assembly which primarily utilizes forces other than gravity forces in dispensing mix from a bowl but does not require a piston assembly operating at high pressures.
Another object of the present invention is to provide a dispensing assembly which can draw mix from a bowl disposed in any position relative to the assembly, including even completely below the assembly and which is self-priming.
Yet another object of the present invention is to provide a dispensing assembly which can be easily cleaned.
A further object is to provide a dispensing assembly which includes a bowl cover adapted to descend and wipe clean the inside as mix is removed from the bowl.
Still yet another object of the present invention is to provide a dispensing assembly which operates at low pressures but enables quick dispensing of mix in measured quantities.